Scientists are developing a technique which they hope will make drug testing safer, following the London trial which left six men seriously ill.

Southampton University researchers are working with scientists from the drugs firm AstraZeneca to develop a technique called "microdosing".

It means patients are exposed to tiny amounts of a drug, compared to conventional testing.

It is hoped it would make it far less likely people would fall seriously ill.

In March this year six healthy volunteers were taken ill when they took part in a drug trial run by the firm Parexel in its unit at Northwick Park Hospital in London.

It happened because the drug, made by the German firm TeGenero, was so specific to humans that its harmful effects didn't show up when it was given to animals.

'Worrying signs'

Hundreds of drugs are tested safely on people each year.

We can monitor at a local level if the tissue is reacting and producing chemicals that in larger quantities might put the individual at risk

Dr Geraldine Clough, Southampton University

But the next generation of medicines is likely to include more human-specific drugs.

That's why researchers at Southampton General Hospital are developing a safer system.

Instead of injecting the drug into the patient - researchers send it through the skin.

The advantage of this technique, known as microdosing, is that hundreds of times less of the drug is needed.

It doesn't go through the patient's body. Instead it passes through the skin.

Consequently it doesn't spread much beyond the test area.

The researchers then analyse what comes out to see if there are any worrying signs.

'Bridging the gap'

According to Dr Geraldine Clough, her system can test for a hundred different chemicals.

She said: "We can monitor at a local level if the tissue is reacting and producing chemicals that in larger quantities might put the individual at risk."

AstraZeneca is among the companies trying to develop more human specific drugs.

These could lead to better treatments for some cancers and arthritis.

But according to a spokesman for the firm, the progress of new medicines could be blocked if dangerous side effects are not spotted first in animal tests - as happened at Northwick Park.

He said: "This is a technique that can potentially bridge the gap in some case by case examples when the biology from animals may not fully translate into the biology of humans"

The research is in its early stages. But scientists believe that it will lead to a safer way to test the next generation of advanced new medicines.

News of the research comes as a scientist revealed tests he did a decade ago on a drug produced similar results to those seen in the Northwick Park trial.

Terry Hamblin, a professor of immunohaemotology at the University of Southampton, said a 1993 trial he carried out left a terminally-ill cancer patient with the shivers, a fever and low blood pressure, leading him to abandon the test.

Professor Hamblin has submitted his evidence to the committee set up by the government to examine early trials.